Revelation 7 describes two different groups of people who repent during Great Tribulation. The first group is identified as 144,000 Israelites (Rev. 7:4), the second as “a great multitude.”
“After these things I looked, and behold a great multitude which no one could number, of all nations, tribes, peoples and tongues, standing before the throne and before the Lamb.” (Rev. 7:9a)
This “great multitude”, like the 144,000 Israelites are “of” or come “out from” a larger combine group of “nations, tribes, peoples, and tongues”.
In Revelation 7:13, one of the twenty-four elders asks John two questions concerning this innumerable group of people.
“Then one of the elders answered, saying to me, “Who are these arrayed in white robes, and where did they come from?”
When John is unable to provide any answers, the elder answers the questions for him.
“These are the ones who come out of the great tribulation, and washed their robes and made them white in the blood of the Lamb.” (verse 14b)
The Bible is specific these people come out of or out from Great Tribulation, the same event Christ spoke of in Matthew 24:21.
This “great multitude” represents Gentiles (non-Israelites), who come to repentance during three and half years of Great Tribulation. Through the two witnesses they come to learn in Christ’s name there is “no other name under heaven” by which they can be saved. (Acts 4:12)
Their white robes symbolize their repentance, God’s forgiveness of sin and obedience to God's commandments. (Rev. 19:8, 14, Psa. 119:172b)
While these Gentiles have repented of their sins, they have not yet received God’s Holy Spirit.
“For the Lamb who is in the midst of the throne will shepherd them and lead them to living fountains of waters.” (verse 17a; John 7:38-39)
What is the timing of events affecting the “great multitude”?
Revelation 7:1-8 occurs prior to the end of the third year of Great Tribulation. The verses 9-17 follow six months later at the end of Great Tribulation. This “great multitude” of Gentiles is not given protection by God during Great Tribulation, but are protected during the Day of the Lord.
Isaiah 49 shows God the Father will use Jesus Christ to raise up the tribes of Israel and be a light to the Gentiles at His Second Coming.
“And now the Lord [God the Father] says, Who formed Me [Jesus Christ] from the womb to be His [God the Father’s] servant, To bring Jacob back to Him, So that Israel is gathered to Him, Indeed He says, ‘Is it too small a thing that You should be My Servant To raise up the tribes of Jacob. And to restore the preserved ones of Israel; I will also give you as a light to the Gentiles, That you should be My salvation to the ends of the earth.” (Isa. 49:5a, 6)
Isaiah 49 ties directly into the events of Revelation 7.
“They shall neither hunger nor thirst, Neither heat nor sun shall strike them; For He who has mercy on them will lead them, Even by the springs of water He will guide them.” (Isa. 49:10; Rev. 7:16-17)
Verses clearly show the “great multitude” are human beings, susceptible to hunger, thirst and pain. Coming out of great tribulation is going to be a very traumatic experience for these people causing many tears to be shed.
Only those of the first resurrection will be spirit-born members of God’s family immediately after the Great Tribulation. (Matt. 24:29-31; I Co 15:23, 52; I Thes. 4:16-17)
This means immediately after Great Tribulation, the 144,000 Israelites and great multitude of Revelation 7 will still be human beings. Both groups will repent during Great Tribulation, but neither will receive God’s Holy Spirit until after God’s Kingdom is established on the earth. (Acts 2:16, 19-21, 17-18; Dan. 12:12)